This is a large member of the sedge family (Cyperaceae) growing up to 6 feet tall and often forming dense colonies as it spreads by rhizomes. The narrow leaves are long (up to 2 feet) and tend to droop at the tip.

Woolgrass flowers from August to October. Spikelets are in a complex umbel and the mature wooly-looking spikelets at the ends of drooping stems give the plant its name. The flowers are wind-pollinated and the fruit is clustered and seed-like.

Woolgrass provides food, shelter and perches for a variety of wetland fauna. The edible roots are high in starch and were eaten by Native Americans, who used to eat them whole, like potatoes, or ground into flour.

The white flower in the photograph, which was taken in July, is swamp rose mallow.